Polychlorinated biphenyls chemical properties

In earlier editions of the Eniyclopedia there have been articles covering the properties, manufacture, capacities, etc, of polychlorinated biphenyls (PCBs), chlorinated naphthalenes, benzene hexachloride, and chlorinated derivatives of cyclopentadiene. These materials are no longer in commercial use because of their toxicity. However, they stiU impact on the chemical industry because of residual environmental problems. Their toxicity and environmental impact are discussed (see Cm.OROCARBONSANDCm.OROHYDROCARBONS, TOXIC aromatics). 

PCBS (polychlorinated biphenyls) Toxic synthetic chemicals with excellent heat resistance and low electrical conductivity properties. Now little used but considerable quantities remain in old electrical equipment. Produces dioxins and polychlorinated dibenzo-furans when burned below 1200°C. PCBs are toxic and bio-accumulative. 

The polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs) are indnstrial chemicals that do not occur naturally in the environment. The properties, uses, and toxicology of the PCBs are described in detail in Safe (1984), Robertson and Hansen (2001), and Environmental Health Criteria 140. PBBs are described in Safe (1984) and Environmental Health Criteria 152. 

Burkhard, L.P. (1984) Physical-Chemical Properties of the Polychlorinated Biphenyls Measurement, Estimation, and Application to Environmental Systems. Ph.D. Thesis, University of Wisconsin-Madison, Wisconsin. 

Metcalfe, D.E., Zukovs, G., Mackay, D., Paterson, S. (1988) Polychlorinated biphenyls (PCBs) physical and chemical property data. In Hazards, Decontamination and Replacement of PCB A Comprehensive Guide. Crine, J.P., Ed., pp. 3-33, Plenum Press, New York. 

The applicability of using these interdisciplinary approaches, which include incorporation of various physical and chemical properties of the pollutants, QSARs/QSPRs and multicomponent joint action modeling are discussed and evaluated using a group of toxic and carcinogenic pollutants, i. e., polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs). 

Shiu, W.Y. and Ma, K.C. 2000, Temperatrrre dependence of physical-chemical properties of selected chemicals of envirorrmental interest. II. Chloroberrzenes, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxirrs, and dibenzofurarrs. J. Phys. CherrL Ref. Data 29 387-462. 

The technology primarily treats clays because their physical and chemical properties, such as external and internal active surfaces produced by their fine crystalline structure, make them difficult to decontaminate. ARC asserts that pilot studies showed that the technology works well on perchloroethylene (PCE), xylene, phenols, and polychlorinated biphenyls (PCBs). 

PCB organic compounds found as soil and water contaminants continue to grow each year. They include polychlorinated biphenyls (PCBs), phenols, cyanides, plasticizers, solvents, and numerous industrial chemicals. PCBs were historically used as coolants in electrical transformers and are also known by-products of the plastic, lubricant, rubber, and paper industries. They are stable, lipophilic, and break down only slowly in tissues. Because of these properties they accumulate to high concentrations in fish and waterfowl in 1969 PCBs were responsible for the death of thousands of birds in the Irish Sea. 

Mackay and Shiu (1981) and Shiu and Mackay (1986) reviewed the physical-chemical properties of a variety of organic chemicals, polychlorinated biphenyls, and recommended H from a selected value of vapor pressure and aqueous solubility. Eastcott et al. (1988) and Suntio et al. (1988) also gave H for hydrocarbons and pesticide chemicals, respectively. Mackay, Shiu, and Ma (1992a, 1992b, 1993, 1995, 1997) compiled physical-chemical properties, including Henry s law constants for many organic chemicals of environmental interest. 

Mackay, D., W.-Y. Shiu, and K.C. Ma. 1992a. Illustrated Handbook of Physical - Chemical Properties and Environmental Fate of Organic Compounds. I. Monoaromatic Hydrocarbons, Chlorobenzenes and Polychlorinated Biphenyls. Lewis Publishers, Boca Raton, Florida, 697 pages. 

Li, N., Wania, F., Lei, Y.D., Daly, G.L. (2003) A comprehensive and critical compilation, evaluation, and selection of physical-chemical property data for selected polychlorinated biphenyls. J. Phys. Chem. Ref. Data 32, 1545-1590. 

Mackay, D., Shiu, W.Y. (1977) Aqueous solubility of polynuclear aromatic hydrocarbons. J. Chem. Eng. Data 22, 399—402. Mackay, D., Shiu, W.Y, Billington, J.W., Haung, G.L. (1983) Physical chemical properties of polychlorinated biphenyls. In Physical Behavior of PCBs in the Great Lakes. Mackay, D., Paterson, S., Eisenreich, S.J., Simmons, M.S. Eds., pp. 59-69, Ann Arbor Sci. Publ., Ann Arbor, Michigan. 

Laboratory tests have to be performed for materials, intermediates and additives. In these tests the chemical properties are checked, the ultimate biodegradability is verified and the disintegration properties are determined. Chemical testing serves to ensure that neither harmful organic substances, such as polychlorinated biphenyl (PCB) and dioxins, nor heavy metals, such as lead, mercury and cadmium, pass into the soil via the compost. 

Dioxin A family of chemicals with related properties and toxicity. There are 75 different dioxins, or polychlorinated dibenzodioxins (PCDDs) 135 different furans, or polychlorinated dibenzofurans (PCDFs) and 209 different polychlorinated biphenyls (PCBs). Each different form is called a congener, a member of a family of compounds known chemically as dibenzo-p-dioxins. Concern about them arises from their potential toxicity as contaminants in commercial products. Tests on laboratory animals indicate that it is one of the more toxic anthropogenic (man-made) compounds a term used interchangeably with 2,3,7,8-tetrachlorodibenzo-p-dioxin or TCDD Disease prevention Measures used to prevent a disease or reduce its severity Dispersoids The particles of a dispersion... 

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